Heat treating trays



March 10, 1964 M. N. ORNITZ ETAL 3,124,339

' HEAT TREATING'TRAYS Filed Sept. 10, 1958" 2 Sheets-Sheet 1 I0 I35 l0 w I i 5 1r. 1 E L 21 I F|g.2. E

l4 l3 |O In a: 1:: a2! a" u: u n: n Fl INVENTORS' Martin N.Ornitz Edward 'IZBetzig ATTORNEYS United States Patent 3,124,339 HEAT TREATING TRAYS Martin N. Ornitz, Wilkinshurg, and Edward T. Betzig, Pittsburgh, Pa, assignors to Blaw-Knox Company, Pittsburgh, Pa, a corporation of Delaware Filed Sept. 10, 1958, Ser. No. 760,263 2 Claims. (1. 263-47) This invention relates to heat treating trays and particularly to trays for supporting articles to be heat treated in heat treating furnaces, as, for example, in continuous furnaces having doors at each end and rails or rollers therein to support and carry the trays bearing the articles to be treated for passage through the furnace. The trays may be moved through the furnace in series, the doors being opened to admit a new tray and to remove the finally heated tray. Generally, the trays leaving the furnace pass through a water or an air quench. The trays are thus subject to severe thermal shock and are likely to fracture due to the high thermal stresses which occur in the several parts or" the tray. Trays constructed according to our invention may also be immovable worksupporting sections in other types of heat-treating furnaces.

Annealing and heat treating trays have heretofore been used. Such trays are generally made in the form of a grill or a grating integrally cast of a heat resisting steel. Such trays are very susceptible to failure due to the aforementioned thermal shock. Modifications of such integrally cast structure have been proposed in which intersecting members may move difierentially in an effort to overcome the problem of failure from thermal shock. For example, Menough Patent 2,710,746 provides a construction in which the intersecting members are not rigidly secured together.

The present invention provides a structure differing significantly from the prior art structure and having a unique articulated construction of simple, effective, inexpensive form relatively free at the joints between members. In the present invention, the members are free to independently undergo such thermal deflection as may be imposed on them in service, yet the structure is strong, durable, simple and easy to assemble, so that the cost is low.

We provide a plurality of spaced substantially parallel load bearing elements, each having therethrough a plurality of slots at spaced intervals along its lengths, a plurality of spaced substantially parallel cross tie elements disposed at substantially right angles to the load bearing elements and extending through the slots therein, the cross tie elements being notched at spaced intervals along their lengths whereby the notches embrace the load bearing element adjacent the slots therein, in an interlocking engagement, a keeper means extending through the slots of the load bearing elements substantially parallel to the cross tie elements whereby the load bearing elements are restrained from substantial longitudinal movement and hence in fixed relationship with the cross tie elements, and keeper securing means whereby the keeper is restrained from substantial longitudinal movement.

Preferably, the slots receiving the cross tie elements are in partial registry with each other and the slots receiving the keeper means are in full registry with each other whereby, when the keeper means is extended through the fully registered slots of the load bearing members, a portion of the sides adjacent the slots in partial registry will be interlocked in the notches of the cross tie elements, some interlocking on one side of the cross tie elements and some interlocking on the other side of the cross tie elements. In a preferred form alternate slots interlock on one side of the cross tie members while the other alternate slots interlock on the opposite side of the cross tie members.

In the foregoing general description, certain objects of the present invention have been outlined. Other objects, advantages and purposes will be apparent from a consideration of the following description and the accompanying drawings in which FIGURE 1 is a top plan view of a tray according to this invention;

FIGURE 2 is an end elevation of the tray of FIGURE FIGURE 3 is a side elevation of the tray of FIG- URE 1;

FIGURE 4 is a partial section on the line IV-IV of FIGURE 2;

FIGURE 5 is a partial section on the line V-V of FIGURE 1;

FIGURE 6 is a side elevation of a second embodiment of this invention; and

FIGURE 7 is a section on the line VII-VII of FIG- URE 6.

Referring to the drawings, we have illustrated a tray having parallel load bearing elements 10 having a plurality of slots 11 and 12 at spaced intervals along its length, the slots 12 being longer than the slots 11. Each of the slots 11 is adapted to be in registry with an identical slot in each of the parallel load bearing elements 10 and adapted to receive a keeper member 13. Each of the slots 12 in one load bearing member is adapted to be in registry with the slots 12 of each alternate member and in partial registry With the slots in each adjacent load bearing member. The slots 12 are adapted to receive cross tie elements 14 having notches 15 at spaced intervals along their length adapted to coincide with the slots 12 so that a portion of the sides of the slots 12 in alternate load bearing elements are in engagement with the notches 15 on one side of the cross tie elements 14 and the opposite sides of the slots 12 of the other load bearing elements 119 are in engagement with the opposite sides of the corresponding notches 15 of the cross tie elements.

The structure of the invention is assembled by placing the load bearing elements 19 in staggered relation so that the slots 12 are in alignment. The cross ties 14 are threaded through the slots 12 with the notches 15 in alignment with the web portion 1th: of the load bearing elements 111. The load bearing elements are then shifted so that the ends are in alignment, as illustrated in FIG- URE 1. This brings the edges of slots 12 of alternate load bearing elements it? into contact with opposite sides of notches 15 in the cross ties 14 and brings each of the slots 11 into alignment. The keeper element 13 is then threaded through the slots 11 and is fixed to the outside load bearing elements 119 by a keeper securing means such as the weldment 16. This locks the entire tray assembly into an integrated whole in which the junctions of the cross tie elements and the load bearing elements are interlocking but are not rigidly secured together so that there is sufficient freedom of movement to eliminate failure from thermal shock.

It is obvious that the cross tie elements 14- and the keeper elements 13 need not be alternately spaced, as shown in the preferred form, but may be spaced at such intervals as seem desirable for the particular conditions involved. It is also obvious that the weldment 16 need not be at the ends of the keeper elements 13 but may be suitably located along the length of the keeper element in relation to the load bearing elements, or that other keeper securing means may be used.

In the embodiments illustrated in FIGURES 5 and 6, We have illustrated load bearing elements 50, having elongated slots 51 in the webs thereof. Cross tie elements 52 having notches 53 are inserted through these slots 51 until the notches are aligned with the wall of the slots. The cross ties are then moved until the notches engage the edge of the slot. A keeper 54 is inserted through the slots 51 behind the cross tie 52 and spot welded 55 to the cross tie element. This locks the cross tie against removal but permits freedom of movement between it and the load bearing element.

In the embodiment described and illustrated the load bearing elements ltl are symmetrically shaped beam sections and the slots 11 and 12 therein are at substantially the neutral axis of the members 10 so that the trays are reversible. They may therefore be inverted from time to time, as deflections due to creep of the alloy members under load develop, so that deflections reverse in direction and the tray will straighten itself. Our articulated construction is particularly suited to such reversible trays, which are preferred for most applications; but our invention is also useful without limitation to this reversible feature.

While we have illustrated and described a preferred form of our invention, it will be understood that the invention may be otherwise embodied within the scope of the following claims.

We claim:

1. An annealing tray and the like comprising a plurality of substantially parallel load bearing elements, each having a plurality of slots at spaced intervals along its length, a plurality of spaced substantially parallel cross tie elements having notches spaced along their lengths, the cross tie elements being horizontally disposed at substantially right angles to the load bearing elements through the slots therein whereby the notches loosely embrace a portion of one side adjacent each slot in loose interlocking engagement, said notches engaging the same side of corresponding slots in each load bearing element and a keeper extending through the slots beside the cross tie elements on the side thereof opposite the notches and fixed thereto, whereby the load bearing elements are restrained from relative longitudinal movement to hold the cross tie notches in engagement with the load bearing element.

2. An annealing tray and the like as claimed in claim 1 wherein the keeper means is a round bar welded at spaced points to the cross tie elements.

References Cited in the file of this patent UNITED STATES PATENTS 1,428,230 Hess Sept. 5, 1922 2,710,746 Menough June 14, 1955 2,834,267 Beebe May 13, 1958 

1. AN ANNEALING TRAY AND THE LIKE COMPRISING A PLURALITY OF SUBSTANTIALLY PARALLEL LOAD BEARING ELEMENTS, EACH HAVING A PLURALITY OF SLOTS AT SPACED INTERVALS ALONG ITS LENGTH, A PLURALITY OF SPACED SUBSTANTIALLY PARALLEL CROSS TIE ELEMENTS HAVING NOTCHES SPACED ALONG THEIR LENGTHS, THE CROSS TIE ELEMENTS BEING HORIZONTALLY DISPOSED AT SUBSTANTIALLY RIGHT ANGLES TO THE LOAD BEARING ELEMENTS THROUGH THE SLOTS THEREIN WHEREBY THE NOTCHES LOOSELY EMBRACE A PORTION OF ONE SIDE ADJACENT EACH SLOT IN LOOSE INTERLOCKING ENGAGEMENT, SAID NOTCHES ENGAGING THE SAME SIDE OF CORRESPONDING SLOTS IN EACH LOAD BEARING ELEMENT AND A KEEPER EXTENDING THROUGH THE SLOTS BESIDE THE CROSS TIE ELEMENTS ON THE SIDE THEREOF OPPOSITE THE NOTCHES AND FIXED THERETO, WHEREBY THE LOAD BEARING ELEMENTS ARE RESTRAINED FROM RELATIVE LONGITUDINAL MOVEMENT TO HOLD THE CROSS TIE NOTCHES IN ENGAGEMENT WITH THE LOAD BEARING ELEMENT. 